(316) Risk of Retinal Vein Occlusion in Colorectal Cancer Patients Using Anti-Vascular Endothelial Growth Factor: A Population-Based Cohort Study

Saturday, August 27, 2022

8:00 AM – 6:00 PM CEST

Location: Hall C

Publication Number: 990

Presenting Author(s)

Wan-Ju Annabelle Annabelle Lee, MD. PhD.
– Dr., Department of Ophthalmology, Chi Mei Medical Center, Tainan, Department of Optometry, Chung Hwa University of Medical Technology, Tainan, Tainan, Taiwan (Republic of China)

Co-Author(s)

Chung-Han Ho
– Associate Research Fellow, Department of Medicine Research, Chi Mei Medical Center, Tainan. Taiwan, Tainan, Taiwan (Republic of China)
Wei-Pang Chung
– Department of Oncology, National Cheng Kung University Hospital, Tainan, Taiwan, Tainan, Taiwan (Republic of China)
Shih-Chieh Shao, PhD candidate
– Pharmacist, Keelung Chang Gung Memorial Hospital, Tainan, Tainan, Taiwan (Republic of China)
Edward Lai, PhD
– Associate Professor, National Cheng Kung University, National Cheng Kung University, Tainan City, Tainan, Taiwan (Republic of China)

Background: The use of anti- vascular endothelial growth factors (VEGFs) treatment had been reported to increase the risks of thromboembolic events. Therefore, the use of anti-VEGFs for patients with colorectal cancers (CRC) raised the concern of the increased risk of retinal vein occlusion (RVO), an ocular disease which caused by embolism or venous stasis. This study aimed to evaluate the risk of RVO in patients with CRC treated with anti-VEGFs.

Objectives: To determine the association of anti-VEGF use and RVO in colorectal cancer patients.

Methods: We conducted a retrospective cohort study by analyzing the data from Taiwan’s Cancer Registry and National Health Insurance database (NHID). We selected a cohort of patients newly diagnosed of CRC from 2011 to 2017 and received anti-VEGFs. New case was identified based on 12 months’ washout period. We defined the date of first prescription of anti-VEGF as index date. Four patients diagnosed with CRC but without an exposure of anti-VEGF were randomly selected as the control group. The study outcome was the incidence of RVO defined by the ICD-9-CM (362.35 and 362.36) or ICD-10-CM codes (H3481 and H3483). Patients were followed from their index date until the occurrence of RVO, death, or the end of the study period. Covariates included patients’ age at index date, sex, calendar year of CRC diagnosed, stage of CRC and comorbidities related to RVO. We used multivariable Cox proportional hazards regression model to calculate hazard ratios (HRs) and 95% CIs with adjustments of all covariates to compare the risk of RVO between anti-VEGF group and control group.

Results: We identified a total of 6285 patients in anti-VEGF group and 37250 patients in control group with the mean age of 59.49 ±12.11 and 63.88 ±13.17 years respectively. The incidence rates were 1.06 per 1000 person-year for anti-VEGF group and 0.63 per 1000 person-year for control group. There was no statistically significant difference for the RVO risk between anti-VEGF and control group (HR, 2.21; 95% CIs, 0.87-5.61).

Conclusions: Our results indicated no association between the use of anti-VEGF and the occurrence of RVO among CRC patients, although the crude incidence rate of RVO was higher in patients receiving anti-VEGF comparing with control patients. Future study with larger sample size is required to reassure our findings.